Parametric studies on Heat pipe

Abstract

In the textile industry lots of energy is being wasted along with flue gases which are used for maintaining the moisture in the fabrics. To recover the heat from the flue gases heat pipe heat exchanger can be used. The objective of the present study is to study the effects of various parameters on Copper heat pipe viz. amount of working fluid (water) filled in the heat pipe (20%, 30%, 40%), pressure/vacuum inside the heat pipe (0.2 bar, 1 bar, 1.8 bar), number of layers of wick (0, 1, 2) and inclination of heat pipe (0o, 45o, 90o). All the heat pipes were developed indigenously. In the heat pipe heat exchanger, heater was provided on the evaporator section and heat was transferred to the water. Arrangement is made for maintaining the constant head and hence flow rate in the heat pipe heat exchanger. To optimize the number of experiments, design of experiment technique was applied using Design Expert software by center composite method (face centered method); which has decreased number of experiments from 81 to 30. Based on the experimental results, an empirical model consisted of 8 significant terms was developed. The percentage deviation between actual efficiency and efficiency predicted by the model was found within ±10%. Among various parameters, the amount of working fluid filled in the heat pipe was found to be most important for the better performance of the system. The maximum efficiency was found as 86.17% with 40% filling of fluid and 1 wick layer at 1 bar and 45o inclination of heat pipe.